The present invention relates to a bending press for bending a sheet material, partitioned tools for use in the bending press and methods and apparatus for exchanging the tools used in bending press.
Press brakes for bending sheet materials are provided with upper and lower tables opposed to each other that are supported by side frames, where the upper table or the lower table is made free to move upwards or downwards. The lower part of the upper table is provided with an upper tool holder for removably holding the upper tool, and the upper part of the lower table is provided with a lower tool holder for removably holding the lower tool, which cooperates with the upper tool. A bending process is then performed by inserting a sheet work material in between the upper tool mounted on the upper tool holder of the upper table and the lower tool mounted on the lower tool holder of the lower table.
Conventionally, the exchange of the upper and lower tools by dismounting and mounting the upper and lower tools of the upper and lower tables were carried out manually. The upper and lower tools includes divided tools divided into a plurality of elements and long tools, but the upper and lower tools are in general are heavy, and the dismounting and mounting in exchanging the upper and lower tools onto the table was a burdensome work.
Thus techniques to exchange the upper and lower tools by dismounting and mounting the tools relative to the upper and lower tables automatically have been developed. Related prior art references are JP55-45288, JP57-37408 and JPU63-21932. Also prior art references related to the tool of the present invention includes for example JP2771064 and the like.
Now in performing a bending process on a work by a press brake, there are cases where, for example, tools of different lengths are mounted separately at a plurality of locations on the tool holders of the upper and lower tables, and the bending process is performed on a workpiece successively by the each processing station. The prior art references, however, all apply only to the case where there is only a single tool mounting location for the upper and lower tables and not for the case with a plurality of processing stations, and therefore the exchange of tools for the upper and lower tables with plural number of processing stations are still made manually.
The present invention was made in view of the heretofore-aforementioned problems. That is, the first press brake is a press brake where the upper table provided with the upper tool holder and the lower table provided with the lower tool holder face each other in the vertical direction, and one of them to freely movable upwards and downwards. In the rear of the upper table, there are provided an exchange upper tool support for removably supporting a plurality of divide upper tools and an upper tool exchange device to exchange the divided upper tool between the exchange upper tool support and the upper table. In the rear of the lower table there are provided an exchange lower tool support for removably supporting a plurality of divided lower tools and a lower tool exchange device to exchange the divided lower tool between the lower table and the exchange lower tool support.
The second press brake is structured so that each upper and lower exchange tool supports are made to move upwards and downwards freely so that by providing a tool support which may move upwards and downwards freely to the upper and lower tool exchange device, the upper and lower divided tools may be supported freely.
The 3rd press brake is a press brake where the upper table provided with an upper tool holder and the lower table provided with a lower tool face each other downwards and upwards and where either the upper table or the lower table is made free to move upwards and downwards and where the left-right direction upper guide provided in the rear part of the upper table is made to protrude largely from the sides of the upper table in the left and right directions, and in order to exchange a plural number of divided upper tools on the upper table, an exchange upper tool support part which supports and allows attachment and detachment of a plural number of divided upper tools is provided on the protruded side part at a position which may be changed freely, and in order to exchange the divided upper tools between the exchange upper tool support part and the upper table, an upper tool exchange device free to move in the left-right directions is provided on the upper guide part, and the lower guide part which is provided in the rear of the lower table and is made to protrude largely from the lower table sides in the left-right directions and in order to exchange a plural number of divided lower tools on the lower table, an exchange lower tool support part is provided on the protruded side part at a position which may be changed freely, and in order to exchange the divided lower tools between the exchange lower tool support and the lower table, a lower tool exchange device free to move in the left-right directions is provided on the lower guide part.
In the 4th press brake, in the rear of the part of the upper guide protruding from the sides of the press brake described above, an upper tool housing section is furnished which houses a plurality of exchange upper tool support parts which support a plurality of divided upper tools which may be freely attached or detached and a tool support exchange device made free to move forward and backward to exchange the exchange upper tool support between the housing and the protruded part of the upper guide.
The 5th press brake is provided with a rotating part to turn round the front and rear sides of the exchange upper tool support part of the tool support exchange device in the press brake described above.
In the 6th press brake, below the protruded side part of the of the lower guide part in the press brake described above, a lower tool housing is provided which houses a plurality of exchange lower tool supports which support plurality of divided lower tools which may be attached or detached freely, the lower tool housing being made free to move back and forth and to thrust the exchange lower support positioned below the lower guide part on the protruded side part upwards, an exchange lower tool support lift is provided.
The 7th press brake is equipped with a temporary work holding device that may hold the work and a bending robot that supplies the work in between the upper and lower tools.
The divided tool of the present invention is arranged so that, in the divided tool freely exchangeable by mounting and dismounting from the tool holder of the press brake, the divided tool is provided with a shank part which maybe engaged and disengaged from the mounting groove of the tool holder and, together with a work processing part to process the work and a concave engage part to which a lock piece, provided on the wall of the mounting groove and made free to appear or disappear, may be engaged freely is provided on the shank part and an engagement piece which may be made to turn up or hidden freely is provided on the shank part on the engage groove of the wall of the mounting groove and also an insertion hole for the tool hold to hold the divided tool and also to turn up and hide the engagement piece are provided near the shank part.
The first tool exchange device of the present invention is structured so that, in the tool exchange device for exchanging the divided tools between the tool holder device provided on the bending press and the exchange tool support which supports a plurality of divided tools free to attach and detach, on one side of the ends of the divided tool, a hook support with an abutted protuberance which may be abutted freely and a hook part with a curved point which may be abutted free to move in the long direction of the hook support and also to the other sides in front or rear of the divided tool, and are provided so that the divided tool may be held between the front and rear part by the abutted protuberance and the front edge part of the hook material.
In the second exchange device, in the tool exchange device described above, together with providing an insertion hole in the front to rear direction formed on the divided tool in which the hook support material and the hook material may be inserted freely, the hook material is made free to move in the direction crossing the long direction of the hook material and part of the hook support material is made in a wedge form so that the hook support material and the hook material may be engaged with little play in the insertion hole.
In the third tool exchange device, in the aforementioned tool exchange device, to at least one of the curved points provided on the abut protuberance or the hook material, an operation part is provided to turn up and down the engagement piece provided on the divided tool.
Also other characteristic features of the present invention are a bending press with at least one bending station to mount a plurality of divided tools (1) and,
a bending press system provided with a tool housing device (65, 123) to house the divided tools of the bending press,
a tool exchange device (61, 143) to move the divided tools between the tool housing device and the bending station and to mount the divided tools onto the bending station,
and a system provided with a first memory means (403) which stores the housing position of each divided tools housed in the housing device,
a second memory means (405) to store the bending line length, flange length and the bending angle,
and a first calculation means (407) to calculate, based on the bending line length, flange length and the bending angle, the types of tools (cross section shape) of the divided tools to be positioned on the bending station and the bending station length,
and a second calculation means (409) to calculate, based on the bending station tool types and length, the arrangement of each divided tool on the bending station,
and a NC control device (411) to control the tool exchange device so that each divided tool is moved from the housing device to the determined arrangement position.
By this system, the divided bending tool may be installed automatically on the bending press based on CAD data that specifies the bending product.
In the second calculation means, in calculating the arrangement of each divided tool on the bending station, it is preferable to make reference to the tool data which describes the divided tools housed in the bending station, tool housing, tool magazine.
By this means, the tool arrangement may be determined quickly by use of divided tools that are usable in practice.
Further features of the invention are, in a bending press system where a bending press (1) with at least one bending station for attaching a plural number of divided tools, and
a tool housing (123, 129) which houses the divided tools for the bending press,
a tool exchange device (61, 143) to move the divided tools between the tool housing and the bending station and to attach the divided tools to the bending station,
are provided as a method to attach the divided tools to the bending station,
a stage to memorize the housing position of each divided tools housed in the housing device and,
a stage to determine, based on the bent length of the bending part of the bent product, flange length and the bending angle, the types of the tools (cross section shape) of the divided tools arranged on the bending station and the length of the bending station and,
a stage to determine the arrangement of each divided tool on the bending station based on the tool types of the divided tools to be arranged on the bending station and the length of the station and,
a stage to move each divided tool from the housing position of the housing device to the determined arrangement position by the tool exchange device.
By this method, on basis of the CAD information and the like which specify the shape of the bent product, the divided tools may be installed on the bending station automatically.
In the method, in determining the arrangement of each divided tool on the bending station, it is desirable to use long tools.
This will expedite installment of the divided tools on the bending section.
In using long tools preferentially, it is desirable to use the quotient of the total length of the tool station divided by the length of the tool (for instance 100 mm) as the number of long tools to be used and fill the remaining length with short tools (for instance 10, 15, 20, 25, 30 mm long).
Also in determining the arrangement of each divided tool on the each bending station, it is desirable to arrange the long divided tools on both edges of the station and arrange the short divided tools in between the long divided tools arranged on the both edges.
By the arrangement, a bending section with a clean bending line form may be made.
Also when there is only one long tool on one station, the short tool to positioned on the side of the long tool.
In the stage in arranging the divided tools on the bending station, it is desirable to take into consideration the tool database that shows the divided tools mounted on the bending station and the divided tools housed in the tool housing device or the tool magazine.
This allows the arranging of the tool station using only usable divided tools that are arranged on the bending station or housed in the tool housing device or the tool magazine.
In more detail, in determining the arrangement of each divided tool on the each bending station, after determining the arrangement of the divided tools tentatively, it is desirable to make reference to the memory device which stores the types and number of divided tools mounted on the bending station and the type and number of divided tools stored in the tool housing device and the number and type of divided tools stored in the tool magazine outside the bending press in order to confirm whether all divided tools to be arranged on the tool station exist or not. And, for instance, if there is shortage in the number of long tools necessary, it is desirable to cover the shortage with short tools. That is, for instance, if the divided tool to be placed on the tool stage includes a tool that is not housed in the housing device or the magazine, the arrangement of the divided tools on the each station may be changed. For instance, if there is shortage of long tools of certain types but a large number of short tools of the same type exist in the housing device or the magazine, a plural number of short tools of the same type may be used at the station position where long tools should have been used.
Or if it is found that the designated divided tool does not exist in the tool housing device or the tool magazine after the arrangement of the divided metal has been determined, the lacking tool may be moved from a neighboring tool station.
There is also a case where the order of bending on bending sections is determined according to the bending line length, flange length, bending angle, and the determination of the tool types, bending station length of each station may be made based on these data. In this case, when the problem (including the case where the divided tool to be arranged on the tool station is not housed in the housing device or the magazine) arises, the bending order may also be changed.
The tool housing device is desirably provided with a first housing section (65) positioned on the bending axis of the bending station and a second housing section (123) which is provided with a tool support member (129) for supporting a plural number of divided tools with the same cross section shape. In moving the each divided tool from the housing device to the tool arrangement position on the bending station, it is desirable to house tools of each type (for instance each length or shape) in the second housing section and move a plural number of tools of the same type altogether from the second housing section to the first housing section and, in the first housing section provided at the tool insertion position of the bending station, divide the plural number of divided tools and insert the designated number of divided tools onto the bending station.
By the organization, the mounting time of the divided tools to the bending station may be shortened.
Also in inserting the divided tool from the first housing section to the bending station, after sliding a plurality of long tools collectively from the first housing section (standby station) to the bending station and positioning them at the designated position, make space for short tools at a designated position in between the long tools where the short tools may be inserted and arranged.
Another feature of this invention is a method to determine the order of processing when manufacturing a plurality of bent products. This method may be applied to a bending press system with a bending press provided with at least one bending station for attaching a plurality of divided tools and,
a tool housing device (123, 129) for housing divided tools for the bending press and,
a tool exchange device (61, 143) by which the divided tools may be moved between the tool housing device and the bending station.
Also the method is provided with,
a stage to store in the first memory means each divided tool housed in the bending station and the housing device and the divided tools housed in the tool magazine outside the bending press and,
a stage to determine the tool type (cross section shape) to be arranged on the bending station and the length of the bending station and,
a stage to produce the order of manufacturing data in order to produce the bent product that uses the tool holder mounted on the bending station or the tool housed in the tool housing device before producing the bent product that uses tools housed in the tool magazine outside the bending station.
By this method, a plurality of products may be produced by the bending system quickly.
Another tool exchange mounting method of the present invention where in a press brake where the upper table provided with an upper tool holder and the lower table provided with a lower tool holder are made to oppose each other upwards and downwards and where one of the tables is made to move up and down freely, the case where the exchange of divided tools between the upper and lower tables and the exchange upper tool support which support a plurality of divided upper tools free to attach or detach and the exchange lower tool support with support a plurality of divided lower tools free to attach or detach are made automatically by use of the tool exchange device and a tool exchange and mounting method where divided tools with the smallest tool width are arranged in between a plurality of divided tools.
In the method, it is desirable to move sideward the plural number of divided tools adjacent to each other from the exchange tool support positioned at the side of the tool holder and separate the divided tools from each other on the tool holder and arrange the divided tools with small tool widths in between the separated divided tools.
Another tool exchange method of the present invention is, in the divided tool exchange on the press brake where, by use of the divided tools mounted on the tool holder of the press brake and a plural number of divided tools housed in the tool housing section, divided tools with desired lengths are mounted on the tool holders of the upper and lower table, where the divided tools which compose the entire length of the tool station are selected according to the bending length information, the selected tool station is displayed on the screen together with the work, a divided tool exchange method where the selected divided tools are mounted after moving the divided tools which interfere with the work to a position where it does not interfere.
This tool exchange device of the present invention is a divided tool exchange device in the press brake where, by use of the divided tools and a plural number of divided tools housed in the tool housing which are mounted on the tool holder of the press brake, divided tools with desired lengths are mounted on the tool holders of the upper and lower tables, and is a divided tool exchange device provided with a tool selection means to select from the divided tools mounted on the tool holder and divided tools housed in the housing section, divided tools which constitute the entire length of the tool station in correspondence with the bending line length of the product shape information, and an interference detection means to detect interference between the tools and the work by displaying the tool station selected by the tool selection means together with the work on a screen, and a tool transfer means to transfer the tool detected by the interference detection to be interfering to a non-interfering position.
In the apparatus, it is desirable to take the quotient of the total length of the tool station divided by the length of the longest divided tool as the number of the longest divided tool and to compose the difference in length between the total length and the total length of the longest divided tools by other divided tools.
In the apparatus, when the quotient of the total length of the tool station divided by the length of the longest divided tool is taken as the number of the longest divided tools but when the difference in length between the total length and the total length of the longest divided tools cannot be composed by a combination of other tools, it is desirable to use as the number of longest tools a value equal to 1 subtracted from the number and compose the difference in length between the total length and the total length of the longest divided tools by a combination of other divided tools.
Definitions:
The meanings of terminologies used in this description are as follows.
xe2x80x9cFlange lengthxe2x80x9d: The size of the flange in the direction perpendicular to the bending line.
xe2x80x9c(Divided) tool typexe2x80x9d: The type of the (divided) tool specified by the cross-sectional shape of the bending tool
xe2x80x9cSize of the divided toolxe2x80x9d: The width of the divided tool when mounted on the bending station.
xe2x80x9cUsable (divided) toolxe2x80x9d: (Divided) tools that are held by the factory where the bending press is installed and which are usable by the factory installations and the like.